In the prior art adhesive residues, old asphalt tile, varnish and plastic finishes, and built-up paint have been removed from concrete floors by the application of strong solvents poured on selected concrete surfaces. About one gallon of such solvents were used per hundred square feet. After soaking, the softened material was peeled by hand tools and removed from the surface by flushing with water. All waste material and water was isolated, collected, and disposed as hazardous waste.
A search of the patent literature was made to determine what tools might be available to remove the above materials from a concrete floor. A number of floor cleaner patents were found. For example, U.S. Pat. No. 4,219,898 discloses a floating brush arrangement in which a plurality of brushes are pivotally connected to a bottom face of a floor polishing machine. Each brush is independently connected and is biased downwardly by a toggle type spring so that the brush is capable of tracking on an uneven contour of the floor.
U.S. Pat. No. 3,591,884 is for a machine for pointing ceramic tiles. A rotatable plate has on its underside resilient, slanted steel blades and which are completely covered, on the side facing the material to be processed, with a felt or plastic pad.
U.S. Pat. No. 3,522,679 illustrates a concrete abrading machine which drives a disk having steel rubbing pads attached to its bottom surface. The side edges of the pads are slightly curved and have leading faces rotationally leading the main part of the pad and tapering rearwardly in spiral fashion around the axis of the disk. The leading faces are congruent with the periphery of the disk. During their rotation the pads tend to force material that they engage toward the center of the disk, while rubbing it upon the floor surface.
U.S. Pat. No. 3,361,044 illustrates a cement finishing apparatus having a water tank mounted on the frame from which water can be sprayed onto the fresh cement.
U.S. Pat. No. 2,702,712 discloses mining machine bits or blades with leading and trailing surfaces, the blades being bent and having a hardened insert. There is a support plate for the blade, the support plate having a retaining spring, the spring having an inturned tongue from one end extending into the bit to prevent accidental displacement of the bit from a socket.
U.S. Pat. No. 1,698,611 discloses a biasing means to bias a blade towards a support plate.
U.S. Pat. No. 4,186,967 discloses a rotary scraper having rotary plates with a plurality of cutting bits located angularly around the plates.
the following patents disclose devices similar to those described above:
U.S. Pat. No. Re 19, 613 PA1 U.S. Pat. No. 1,901,681 PA1 U.S. Pat. No. 1,924,582 PA1 U.S. Pat. No. 1,932,319 PA1 U.S. Pat. No. 1,958,077 PA1 U.S. Pat. No. 2,713,757 PA1 U.S. Pat. No. 2,793,476 PA1 U.S. Pat. No. 2,923,107 PA1 U.S. Pat. No. 3,098,329 PA1 U.S. Pat. No. 3,102,372 PA1 U.S. Pat. No. 3,428,984. PA1 U.S. Pat. No. 3,509,648 PA1 U.S. Pat. No. 4,303,362